Well completion apparatus and method

ABSTRACT

Well completion apparatus in which a casing hanger is suspended from a first member of a well tool and a sealing member is suspended from a second member of the well tool. The first and second members are releasably connected whereby upon landing the casing hanger within the well the first member is disconnected from the second member and the sealing member is lowered into sealing position independently of the casing hanger. A portion of the sealing member is rotated to cause an expansion ring to engage an annular groove in the casing head thereby actuating the sealing member and locking the sealing member and casing hanger in position.

mesa-1i.

United States Patent 1 91 [111 3,809,158 Bonds et al. May 7, 1974 [54] WELL COMPLETION APPARATUS AND 3,460,615- 8/1969 Watkins, 166/88 x 3,492,026 1/1970 Ahlstone 285/142 X METHOD 3,528,686 9/1970 Nelson 285/18 [75] Inventors: James Vaull Bonds; John Walton 3,721,292 3 1973 Ahlstone 285/18 x McCaskill, both of Houston, Tex. [73] Assignee: Rockwell International Corporation, Primary Examiner-Henry S. Jaudon Pittsburgh, Pa, Assistant Examiner-Philip C. Kannan 22 Filed: July 27, 1972 7 A CT B A [21] Appl. No.: 275,576 [5 g Well completion apparatus in which a casing hanger is suspended from a first member of a well tool and a [52] U.S. Cl l6268/510, l2686/2l8f2, 126865641052, sealing member is Suspended from a second member 2 l 5/ 06 of the well tool. The first and second members are reg ig i fi 2 4 1 leasably'connected whereby upon landing the casing 1 3 7 5 39 166/86 88 hanger within the well the first member is disconnected from the second member and the sealing memher is lowered into sealing position independently of the casing hanger. A portion of the sealing member is [56] References cued rotated to cause an expansion ring to engage an annu- UNITED STATES PATENTS lar groove in the casing head thereby actuating the 3,421,580 111969 Fowler et al 166/.5 sealing member and locking the sealing member and 3,540,533 ll/l970 Moi-rill casing hanger in position. 3,057,418 10/1962 Koppl 1 3,279,539 l0/l966 Brown et al. 285/142 X 24 Claims, 13 Drawing Figures F 1- a; vs

PATENTEUW 119M SHEET 5 OF 6 1 WELL COMPLETION APPARATUS AND METHOD BACKGROUND OF THE INVENTION 2. Description of the Prior Art In recent years the drilling of sub-sea and other underwater wells for the production of oil and gas has increased greatly requiring special equipment. In an underwater well initially a' conductor casing is jetted or driven into the ocean floor. A riser or casing is then extended from the conductor casing to the drilling platform at the surface. From the drilling means on the surface a hole is drilled in the-ocean floor for the suspension of a casing string within the conductor casing. This casing string is suspended from the conductor casing by means of a casing hanger which is supported by the conductor casing. An inner riser extends from the casing hanger to the drilling surface.

To hold the casing string in place within the newly drilled bore, it is cemented. Cement is passed through the inner riser and down through the casing string. The cement is forced around the lower end of the casing string and into the annulus formed by the earth bore and casing string. By computing the volume of the annulus, it may be determined approximately how much cement is required to reach a certain level in the annulus. After the cement has reached the desired level, the annulus is sealed off above the cement level by means of a sealing element. This sealing element is generally located near the casing hanger.

Most sub-sea hanger systems require that the hanger and sealing element be run separately into the well. To first install the casing hanger, then cement, and then run in the sealing element requires great expense and time. Therefore, it is desirable to run the casing hanger and sealing element into the well in a single trip.

Single trip running tools for running the hanger and sealing element into the well together are shown in U.S. Pat. Nos. 3,638,725; 3,492,026; 3,489,436; 3,468,559; 3,460,615; 3,382,921; 3,335,799; and 3,279,539.

U.S. Pat. Nos. 3,460,615, 3,382,921; 3,279,539; and the Ahlstone U.S. Pat. Nos. 3,638,725; 3,492,026; 3,489,436; and 3,468,559 show a running tool permitting the axial movement of one portion of the running tool with respect to another portion. The Ahlstone U.S. Pat. and U.S. Pat. Nos. 3,382,921 and 3,279,539 show an assembly where the outer portion of the running too] drives the sealing element into sealing engagement with the casing hanger. In the Ahlstone patents and U.S. Pat. No. 3,279,539 the sealing element is connected to the outer portion of the running too].

The Ahlstone patents show a sealing element having two portions connected by ball bearing means. U.S. Pat. Nos. 3,492,026; 3,489,436; 3,468,559; and 3,460,615 show the assembly having a .bowl protector. U.S. Pat. Nos. 3,638,725; 3,492,026; 3,489,436; 3,460,615; 3,382,921; 3,335,799; 3,279,539; and 3,273,646 show the sealing element actuated upon righthand rotation of the driving member. U.S. Pat. Nos. 3,638,725 and 3,279,539 show the disconnection of the running tool from the casing hanger by rotation to set the seal and then a lifting of the running tool.

The prior art assemblies have proven to be inadequate since they require a direct connection between the seal and the casing hanger. Generally, this connection is a threaded engagement between the sealing element and the casing hanger. Such a connection creates difficulties where the sealfails to become established on the first attempt thereby requiring that the seal be removed from the well and reinserted. Upon running the seal in the second time, the prior art connections require the running tool to pick up the lead thread on the casing hanger to threadingly engage the sealing elements onto the casing hanger to set the seal. Where the lead thread has been damaged, the sealing element can never be re-engaged.

A connection between the sealing element and casing hanger requires a special casing hanger since some kind of connection means must be formed on the hanger to connect with the sealing element.

A combined means for compressing the sealing element and for securing the casing hanger in the well is shown in U.S. Pat. No. 3,540,533.

SUMMARY OF THE INVENTION The present invention is an apparatus for installing and sealing a-casing hanger within a casing head. It includes a running tool having an outer portion releasably connected to an inner portion. The outer portion is releasably connected to a sealing member and the inner portion is releasably connected to the casing hanger. Upon landing the casing hanger within the well, the outer portion is disconnected from the inner portion and the sealing member is lowered into position between the casing hanger and easing head. There is no connection between the sealing member and easing hanger, thereby permitting-a standard casing hanger to be used.

The outer portion of the running tool is rotated to the right causing a latch to expand thereby actuating a compression seal attached to the sealing member which then seals the annulus surrounding the casing hanger.

The expanded latch holds the sealing member into position and locks the casing hanger in place'within the well.

The invention has the further advantage that if the seal fails to sealingly engage in the first attempt, the seal can be removed from the well and upon rerunning the seal back into the well, no lead thread need be picked up to re-engage the sealing member and to actuate the seals within the well.

Other objects and advantages of the invention will appear from the following discription.

- BRIEF DESCRIPTION OF THE DRAWINGS For a detailed description of a preferred embodiment of the invention, reference will now be made to the accompanying drawings wherein:

FIG. 1 is a cross-sectional view of the environment in which the present invention operates;

FIG. 2 is a cross-section of a portion of embodiment I after landing the casing hanger;

FIG. 2A is an isometric view of a J-slot connection for a bowl'protector;

FIG. 3 is a cross-section of a portion of embodiment I after lowering the sealing element into position;

FIG. 4 is a cross-section of a portion of embodiment I after expanding the hold down latch;

FIG. 5 is a cross-section of a portion of embodiment I after releasing the sealing element and re-engaging the running tool;

FIG. 6 is a partial cross-sectional view and perspective view of the breech block connection;

FIG. 7 is a cross-section of a portion of embodiment I after releasing the running tool from the casing hanger;

FIG. 8 is a cross-section of a portion of embodiment II after landing the casing hanger;

FIG. 9 is a cross-section of a portion of embodiment II after lowering the sealing element and expanding the hold down latch;

FIG. 10 is a cross-section of a portion of embodiment II after releasing the sealing element and reengaging the running tool;

FIG. 1 l is a cross-section of a portion of embodiment II after releasing the running tool from the casing hanger; and

FIG. 12 is a cross-section of a multiple installation of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is a method and apparatus for running a casing hanger and a sealing member into an oil or gas well on a single trip of the running tool. Although the present invention may be used in a variety of environments, FIG. 1 illustrates the installation of the present invention in the ocean floor of an off-shore well.

Referring to FIG. 1, a guide base 10, conductor casing 12, a well head 14, and a conductor riser 16 are lowered from a drilling means (not shown) such as barge or a bottom supported platform and installed into the sea floor 18. The conductor casing 12 may be driven orjetted into the sea floor 18 until well head 14 rests near the floor, or if the bottom conditions so require, a hole may be drilled for the insertion of conductor casing 12. The riser 16 extends from the well head 14 to the drilling means (not shown).

Drilling apparatus is lowered through riser 16 and casing 12 to drill a bore 20 in the earth for surface casing 22. A surface casing hanger head 24, suspending surface casing 22, is lowered through conductor casing 16 until hanger head 24 lands and is connected to well head 14. A riser 26 is connected to hanger head 24 and extends to the drilling means (not shown).

The drilling apparatus is then lowered through riser 26 to drill a bore 28 for casing string 30.

EMBODIMENT I Embodiment l is illustrated in FIGS. 2-7. In FIG. 1 there is shown generally a casing hanger 32 suspending casing string with a riser or handling string 34 extending to the drilling means. In FIG. 2 there is shown in detail the combination of handling string 34 suspending a well or running too] 36 which in turn suspends a sealing member or packoff 38 and casing hanger 32 in the bore 28 of the well.

The running tool 36 is connected to handling string 34 by means of coupling 42. The upper portion of coupling 42 is a box 44 with interior threads 46 engaging the exterior threads 48 on the pin 50 of the lowermost section of handling string 34. The lower portion of coupling 42 is a pin 52 with exterior threads 54 engaging the interior threads 56 disposed on the upperend 0f running tool 36. The threads 46, 48, 54 and 56 are shown as right hand engageable threads since such is generally the case in oil and gas wells. The connections between the sections of handling string 34 are also right hand engageable connections. This causes the connections to tighten upon the right hand rotation of handling string 34. The advantage of coupling 42 is that it permits the handling string 34 to be of varied diameters. A different sized handling string 34 may be used by merely changing the coupling 42.

The running tool 36 has two principle members, an outer cylindrical portion or nipple 60 and an inner cylindrical portion or mandrel 70.

Nipple 60 has interior threads 56 disposed on its upper end for connection with pin 52 of coupling 42 and suspends packoff 38 at the lower end by means of the connection at 62.

Mandrel is suspended by and connected to nipple 60 by means of a breech block type threaded connection 66 illustrated in detail in FIG. 6 and described in US. Pat. Nos. 3,442,536 and 3,421,580. A plurality of longitudinally extending tooth segments 68 are machined on alternate 30 segments of the exterior of mandrel 70, the arcuate length of the teeth being slightly less than 30. Matching tooth segments 74 are machined in the upper interior of nipple 60. These teeth also have a length slightly less than 30. The teeth shown are generally in the form of a buttress thread, but it will be appreciated that other forms can be used.

The teeth are engaged with each other by lowering the mandrel 70 into the nipple 60 with the teeth segments 68 positioned to pass between the teeth segments 74. The lowest tooth 76 on mandrel 70 has a double width, so that mandrel 70 must be lowered far enough into nipple 60 to engage the double thickness tooth in the double width groove of nipple 60. The mandrel 70 may then be rotated 30 degrees to engage the breech block connection 66. A stop means 72 is provided on mandrel 70 to stop the rotation of mandrel 70 within nipple 60 after the tooth segments 68, 74 have engaged.

The teeth segments 74 of nipple 60 are disposed below threads 56 a sufficient distance to permit the dis connection of the breech block connection 66 and to lower packoff 38 into sealing position as shown in FIG. 3 and yet provide clearance between the upper terminal end of mandrel 70 and the lower terminal end of coupling 42 in the sealing position. The teeth segments 68 are disposed on the uppermost exterior of mandrel 70 to permit the shortest distance between threads 56 and teeth 74 on nipple 60.

An interference seal 78 is provided below teeth seg ments 68 in annular groove 80 in the external surface 82 of mandrel 70. Seal 78 may be in the form of an O- ring or a T-ring which sealingly engages the smooth internal sealing surface 84 of nipple 60. Seal 78 is disposed a sufficient distance below teeth segments 68 such that upon disconnecting breech block connetion 66 and lowering packoff 38 into sealing position, as shown in FIG. 3, seal 78 will always engage some portion of surface 84 and will never contact the lowermost tooth of teeth segments 74. The primary purpose of seal 78 is to permit the pressure testing of packoff 38 after its actuation. It also permits a continuous seal throughout the installation and sealing operation to prevent well fluids and other material from passing through breech block connection 66.

The lower end of mandrel 70 suspends casing hanger 32 by threaded connection 84. The external threads 86 disposed on the lower end of mandrel 70 engage the interior threads 88 disposed in the box 90 forming the upper portion of casing hanger 32. Connection 84 is a left hand engageable threaded connection permitting the unthreading of connection 84 upon the right hand rotation of mandrel 70. Shear means in the form of shear pin 92 passes through box 90 and into bore 91 in mandrel 70 to prevent the premature loosening of connection 84 by any right hand torque inadvertently placed on mandrel 70 during the disconnection of breech block connection 66 hereinafter discussed.

An interference seal 94, in the form of an O-ring or T-ring, is disposed below bore 91 and above threads 86 in an annular groove 96 in the external. surface 98 of mandrel 70. The primary purpose of seal 94 is to sealingly engage the smooth internal surface 100 of casing hanger 32 to permit the pressure testing of packoff 38. Seal 94 also prevents any well fluids or other material from passing through connection 84.

FIG. 2 illustrates the previously described combination landed within the well. The casing hanger 32 has a radially extending annular ridge 102 which engages an internal annular restrictive shoulder 104 on casing hanger head 24. Shoulder 104 provides the support for casing hanger 32 uponengagement by ridge 102.

The cementing operation for cementing casing string 30 into the well requires a passageway from the annulus 106, between casing string 22 and casing string 30, to annulus 108, between riser 26 and riser 34, to flow the returns to the surface. Ridge 102 has apertures in the form of flutes or circulation ports 110 for fluid flow around casing hanger 32.

Mandrel 70 has a reduced diameter portion 112 generally at its mid section between annular groove 78 at its upper end and bore 91 at its lower end which creates annular passageway 118. Reduced diameter portion 112 is adjacent to packoff 38 so that fluid can flow between the interior of packoff 38 and the external surface 114 of reduced diameter portion 112.

A plurality of circulation ports 116 shown in FIG. 2 communicate between annulus 108 and passageway l 18. These permit return fluids to flow up annulus 106, through ports 110, into the passageway 118, and through ports 116 into annulus 108.

The sealing member or packoff 38, suspended by nipple 60, is to be used to seal off the passageway 118 to the flow of fluids after the completion of the cementing operation. Packoff 38 is connected to the lower end of nipple 60 by the connection at 62. A plurality of equally spaced lands 124, alternated with grooves 126, are disposed on the lower end of nipple 60. The upper end of packoff 38 has lands 128 and grooves 130 correlating with grooves 126 and lands 124 respectively thereby forming a type of clutch. This permits a torque to be placed on packoff 38 upon the rotation of nipple 60. Packoff 38 is suspended axially by shear pin 122 passing through land 126 and into a bore 123 in the lower end of nipple 60.

The sealing member 38 has a connector element 132 forming the connection at 62 at its upper end, and which is telescopically received at its lower end by a compression ring 134 which is rotatably connected to the lower end of connector element 132 by ball bearing means 136. Ball bearing means 136 has a plurality of metal balls 138 rotatably mounted in an annular race 140 in the exterior surface of connector element 132 and in annular race 142 in the interior surface of compression ring 134. 7

An inner cylindrical-shaped packing element 150 and an outer cylindrical-shaped packing element 151 are retained against the lower terminal end of compression ring 134 by a cylindrical packing gland'l52. Packing gland 152 has an annular stem 153 received by a correlating annular groove 154 in the terminal end of compression ring 134. Stem 153 is reciprocably retained within groove 154 by means of a plurality of set screws 155 passing through the exterior of compression ring 134 and into groove 154 to be received by correlating vertical slots 156 in the upper portion of stem 153.

Packing gland 152' has an inner and outer annular shoulder 158, 160 respectively supporting packing elements'150, 151 against compression ring 134. Shoulders 158, 160 and the lower end of compression ring- 134 control the expansion of packing elements 150, 151 during compression hereinafter discussed in more detail. v

A hold down and compression means is mounted on sealing member 38 to lock and secure the casing,

threads 170 on the external surface of reduced diameter portion 166. Expandable latch 162 is mounte above actuator nut 164.

Latch 162 is actuated by the right hand rotation of handling string 34. To prevent actuator nut 164 from rotating with connector element 132, nut 164 is mounted on the upper end of compression ring 134 by means of a clutch connection. Finger-like projections 172 extend from the lower end of actuator nut 164 into correlating recesses -174 in the upper portion of compression ring 134. Compression ring 134 and Packing gland 152 are prevented from rotating relative to each other by means of set screws and slots 156.

Packing gland 152 is held stationary by means of another clutch type connection formed with casing hanger 32. A plurality of lugs 176, reciprocably mounted in recesses 178 in the lower portion of retainer ring 152, are biased outwardly by springs 180. Lugs 176 are retained in recesses 178 by means of interlocking ears at 182. Lugs 176 mate in correlating recesses 183 in annular ridge 102 in the sealing position illustrated in FIG. 3 thereby preventing the rotation of Packing gland 152, compression ring 134 or actuator nut 164.

1 Upon the rotation of connector element 132, actuator nut 164 is therefore held stationary as connector element 132 rotates on bearings 138. This causes nut 164 to rise due to right hand threads 168, 170. An annular beveled edge 184 is disposed on reduced diameter portion 166 thereby camming expandable latch 162 outward as nut 164 forces latch 162 upward. An annular groove 186 is disposed in the internal surface of casing head 24 to receive latch 162. Groove 186 has upper and lower frusto-conical shoulders 187 which aid in the reception of latch 162. Latch 162 has a leading beveled edge 163 which engages the interior of groove 1 86 until edge 163 rests against the upper frusto-conical shoulder 187 thereby wedging latch 162 into place as shown in FIG. 4. This causes the nut 164 to halt its upward movement and causes a downward force to be placed on compression ring 134 as nipple 60 continues rotation. Stem 153 moves deeper into groove 154 as compression ring 134 compresses packing gland 150 into sealing engagement with the external surface of casing hanger 32 and with the internal surface of easing head 24.

Upon completion of the activation of packoff 38, it is seen that latch l62 also locks and secures casing hanger 32 against shoulder 104 thereby preventing any movement of casing hanger 32 within the well.

Connector element 132 is provided with means for suspending a succeeding casing hanger. As shown in FIG. 3 an annular shoulder 188 is disposed on the interior of connector element 132 for engagement and support of the next casing hanger to be installed within the well. Annular groove 190 is disposed below shoulder 188 for recovery of the packoff 38 with a secondary recovery tool (not shown). Upon the installation of the succeeding casing hanger, the added weight of the casing string suspended from that casing hanger will add a further load on the packoff 38 and casing hanger 32.

Referring now to FIG. 2 and FIG. 2A, a bowl protector 192 can be added to protect the interior surface 194 of casing head 24. Often damage is caused to critical surfaces by the passage of equipment through the flow bore. The protector 192 is mounted on the upper end of connector element 132 at 196 by a J-slot connection 197. Connection 197 includes a series of J-slots 199 in the lower end of bowl protector 192 which receive correlating pins 201 disposed in reduced diameter section 203 of connector element 132. A connection means is provided on the upper portion of protector 192 for engagement by a fishing tool to remove it prior to the installation of a succeeding casing hanger. FIG. 2 illustrates the connection means as an annular groove 198 with vertical slots 199 disposed in the upper interior surface of protector 192. Stop lugs (not shown) are affixed within groove 198 to form a plurality of J-slots.

In operating the invention, the assembly, including casing hanger 32, sealing member 38, and well tool 36, is connected to the last section of casing string 30. The

first section of handling string 34 is then attached to well tool 36 and the assembly is lowered into the well by adding successive sections onto handling string 34 until the ridge 102 of casing hanger 32 lands on shoulder 104 of easing head 24.

After landing the casing hanger within the well, cement is passed through handling string or riser 34 and down through casing string 30. After the proper volume of cement has been put in the well, a wiper plug (not shown) is put in the well and well fluids are run into the well forcing the cement around the lower end of casing string 30 and into annulus 106 until the cement rises to the desired level.

Referring now to FIG. 3, to seal off annulus 106 nipple 60 is disconnected from mandrel 70 upon a 30 rotation of nipple 60 to disconnect the breech block connection 66. The handling string 34 is then forced rotated by the right hand rotation of handling string 34 causing actuator nut 164 to rise. Latch 162 expands into annular groove 186, and further rotation compresses packing elements and 151. As the packing elements are compressed, they sealingly engage the exterior surface of casing hanger 32 and the interior surface of casing head 24.

The packoff 38 is then tested by applying a pressure in the annulus 108. The flow bore of riser 34 and easing string 32 is then monitored at the surface to detect any leak in the seals 78, 94. If packoff 38 leaks, a pressure drop will be detected in annulus 108.

If a leak is detected, packoff 38 is removed by the left hand rotation of connector element 132 causing actuator nut 164 to descend, releasing latch 162 so that it can retract from annular groove 186 when riser 34 is lifted, to permit packoff 38 to be lifted from the sealing position.

Upward movement of riser 34 is continued until the lower teeth segments 76 are engaged by the shoulder 73 in the nipple 60 below the teeth segments 74. The handling string 34 is then rotated to the right, the teeth segments 74 and 68 acting as a splined connection to drive the left hand thread connection 84, until completely disengaging from casing hanger 32. The well tool 36 may then be lifted from the well and the problems with the sealing of the packoff 38 corrected.

The packoff 38 may be again lowered into the well on nipple 60 and re-engaged in the sealing position as previously described. No lead thread need be picked up to re-engage the sealing member 38 since only the smooth neck of the casing hanger 32 and the smooth bore 194 of the well head 24 with the simple interior annular groove 186 will have to be engaged.

If no leaks are detected, nipple 60 is released from connector element 132 asshown in FIG. 5. Shear pin 122 is broken by applying an upward force on handling string 34, since sealing member 38 is secured by the latch 162.

Breech block connection 66 is then re-engaged and connection 84 is disengaged as previously described to permit well tool 36 to be removed from the well.

EMBODIMENT II In embodiment II a threaded connection 200 and friction set latch connection 202 are utilized to connect nipple 204 with mandrel 206 instead of breech blockconnection 66 as shown in embodiment 1.

Referring now to FIG. 8 the upper portion of mandrel 206 has a reduced diameter section "208 with threads 210 being disposed on the exterior surface of mandrel 206 at the end of section 208. A land 212, disposed on the interior of nipple 204 with threads 214 thereon, engages threads 210 of mandrel 206.

Upon the right hand rotation of nipple 204, threads 210, 214 disengage, and land 212 is received by reduced diameter section 208 as sealing member 220 is lowered into sealing position shown in FIG. 9. Nipple 204 is lowered until frusto-conical shoulder 216 disposed below threads 214 almost engages frusto-conical shoulder 218 disposed on the exterior of mandrel 206 at the lower end of section 208 as shown in FIG. 9 but no engagement is permitted because friction would arise upon rotating nipple 204 thereby inhibiting the segments 225 to provide added friction. The upper interior edge 227 of latch 222 is beveled to engage the upper cam surface 229 of recess 224.

An annular groove 226 is provided in the interior surface of nipple 204 and is adjacent recess 224 when in the sealing position such that the latch 222 expands into groove 226. Recess 224 has a reduced depth portion 231 at its upper end whereby upon setting sealing member 220 and securing casing hanger 230 by rotating handling string 221, the shear pin 232 is broken by lifting nipple 204 thereby disconnecting the nipple 204 from the sealing member 220. Self expanding latch 222 then automatically expands into groove 226. Beveled edge 227 of latch 222 may engage cam surface 229 if necessary to force latch 222 into reduced depth portion 231 as shown in FIG. 10. i

The friction between the inner surface of groove 226, the latch 222, and the inner surface of recess 224 permits the translation of torque from nipple 204 to mandrel 206. Therefore the rotation of nipple 204 breaks shear pin 234 and mandrel 206 is unthreaded from casing hanger 230 due to left hand threaded connection 236. This is shown in FIG. 11.

A threaded connection could be used in place of the friction set latch connection 202 and the breech block connection 66 as shown in embodiments I and II, but it would obviously be less advantageous.

FIG. 12 illustrates a multiple installation of the present invention with casing head 300 supporting casing hanger 302 which suspends casing string 304, and which supports sealing member 306. Latch 308 is shown compressing packing element 310 to sealingly engage casing head 300 and casing hanger 302.

A second casing string 320 is shown suspended from a second casing hanger 322 which is supported by the connector element 312 of packoff 306. Any number of succeeding casing strings can be installed.

While a preferred embodiment of the invention has been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit of the invention.

We claim:

1. Apparatus for installing and sealing a casing hanger within a well comprising:

a sealing member;

a lowering member having a first portion releasably attached to a second portion;

said first portion having first connection means for suspending such casing hanger;

said second portion having second connection means for suspending said sealing member;

means for releasing said first portion from said second portion to lower said sealing member into sealing position; and

10. said sealing member being clear .of such casing hanger prior to being lowered into said sealing position. 2. Apparatus according to claim 1 further including means for providing a continuous seal between said:

first portion and said second portion.

3. An apparatus according to claim 1 further including means for re-engaging said first portion with said second portion.

4. An apparatus according to claim 3 wherein said re-engaging means includes a latch means frictionally wedging between said first portion and said second portion.

5. An apparatus according to claim 1 wherein: said releasing means connects said first portion to said second portion upon a rotation of said first portion of less than 360; and said second connection means disconnects said second portion from such casing hanger upon a rotation of said second portion.

6. An apparatus according to claim 1 wherein said releasing means disconnects said first portion from said second portion upon a rotation of said first portion of less than 360.

7. An apparatus according to claim 6 wherein said releasing means includes a breech block connection having tooth segment means .in the upper interior of said first portion and correlative tooth segment means on the exterior of said second portion.

8. An apparatus according to claim 1 in combination with a casing head having a stop means wherein said sealing memberincludes latch means engageable with said stop means upon rotation of said first portion.

9. An apparatus accordingto claim 8 wherein said sealing member includes a tubular member rotatably connected to a retainer member and said latching means includes a latch member supported by an actuator member; said actuator member being reciprocatably mounted on said retainer member thereby preventing rotation relative therebetween and being threadingly engaged to said tubular member whereby upon the rotation of said tubular member said actuator member moves axially on said retainer member forcing said latchmember to engage said stop member.

'10. An apparatus according to claim 9 wherein said retainer member includes a packing element whereby said element is compressed against a portion of such casing hanger, thereby sealingly engaging both said casing head and such casing hanger, because of the force applied to said retainer member by said tubular member' upon the engagement of said latch member and said stop member.

11. An apparatus according to claim 10 wherein said retainer member further includes an upper annular ring and a lower annular ring; said packing element being positioned between said rings whereby upon the compression of said packing element, said packing element rotates and said retainer member remains stationary. 13. An apparatus according to claim 12 in combination with such casing hanger wherein said anti-rotation means includes a clutch connection between said retainer member and a portion of said casing hanger.

14. An apparatus according to claim 13 wherein said clutch connection includes biased lugs reciprocatably mounted on said retainer member for insertion into correlating recesses in said portion of said casing hanger in said sealing position thereby preventing rotation of said retainer member while in said sealing position.

15. Apparatus comprising a casing hanger having means thereon for supporting a casing therebelow, and means for engaging a surrounding well head for support of the casing hanger on the well head, a running tool extending upwardly from said casing hanger, 1 means on said running tool and said casing hanger for releasably supporting said casing hanger on said running tool, I a compressible packoff surrounding a portion of said running tool, and means on said running tool and said packoff for releasably supporting said packoff on said running tool, the latter means comprising a J-slot connection, whereby said running tool and said packoff may be disengaged and re-engaged for support of said packoff by said running tool upon rotation of said running tool less than one turn, said running too] including a releasable connection intermediate the casing hanger support means and the packoff support means which allows move ment of said packoff longitudinally relative to said casing hanger when said connection is released. 16. A method of installing a casing hanger comprising the steps of:

suspending a sealing member from a first portion of a well tool and a casing hanger from a second portion of the well tool;

lowering the sealing member and casing hanger into the well on the well tool;

landing the casing hanger on the previously installed casing head;

rotating the first portion to disconnect the first portion from the second portion of the well too];

lowering the first portion and sealing member further into the well;

rotating the first portion to set the sealing member within the well;

raising the first portion to disconnect the first portion from the sealing member; and

rotating the first portion to engage the second portion of the well tool and to disconnect the second portion from the casing hanger.

17. A method as defined in claim 16 wherein the first portion is always rotated in the same direction.

18. A method of installing and sealing a casing hanger affixed to and supporting a string of casing in a remote previously installed casing head in a well comprising lowering the casing hanger and a sealing member 6 setting the sealing member,

pressure. testing the sealing member without removing the running tool, unsetting the sealing member and raising it from the well on said running tool, without removing said casing hanger, and

replacing said sealing member with a second sealing member.

19. A method of installing a casing hanger in a casing head comprising the steps of suspending a sealing member from a first portion of a well tool and a casing hanger from a second portion of the well tool,

lowering the sealing member and casing hanger into the well on the well too],

landing the casing hanger on the previously installed casing head,

disconnecting the first portion from the second portion of the well tool,

lowering the first portion and sealing member further into the well,

setting the sealing member within the well,

disconnecting the first portion from the sealing member,

moving the first portion to engage the second portion of the well tool,

disconnecting the second portion from the casing hanger, and

raising the first portion and the second portion of the well tool from the well.

20. Apparatus comprising a casing hanger having means thereon for supporting a casing therebelow, and means for engaging a surrounding well head for support of the casing hanger on the well head,

a running tool extending upwardly from said casing hanger,

said running tool comprising a first portion and a second portion releasable from each other on manipulation of said running tool,

means on the second portion of said running tool and said casing hanger for releasably supporting said casing hanger on said second portion of said running tool, a compressible packoff adapted to provide a seal between said casing hanger and said well head, and

means on the first portion of said running tool and said packoff for releasably supporting said packoff on said first portion of said running tool.

21. Apparatus as defined by claim 20 wherein said second portion of said running tool is telescopically retained within said first portion of said running too].

22. Apparatus as defined by claim 21 wherein said second portion of said running tool is connected to said casing hanger by means of a left-hand threaded connection and a shear pin.

23. Apparatus for setting a casing hanger connected to a casing in a well head located at a remote location below the surface, and setting a packoff to seal between said casing hanger and said well head, comprising an elongate rotatable and reciprocable running tool having a length sufficient to extend from the surface to the well head,

said running tool having a first portion connected to its lower end and a second portion carried by said first portion,

on the first portion of the running too], and

a releasable connection-between said first portion and said second portion operable upon manipulation of said running too] to permit said first portion to move downwardly relative to said second portion and to be rotated relative to said second portion.

24. Apparatus as defined by claim 23 wherein said 'second'portion is telescoped within said first portion and carried on a shoulder therein.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 3 ,809 'l 58 MAY 7 1 974 Patent No. Dated I inventor) JOHN VAULL BONDS; JOHN WALTON MCCASKI LL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Ciaim 1 Line 6, after "said", delete "first" and insert second after "having", deiete "first" and insert second Line 8, after "said", deiete "second" and insert first I after "having", delete "second" and insert first Signed and sealed this 6th day of May 1975.

(SEAL) Attest:

A C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks 

1. Apparatus for installing and sealing a casing hanger within a well comprising: a sealing member; a lowering member having a first portion releasably attached to a second portion; said first portion having first connection means for suspending such casing hanger; said second portion having second connection means for suspending said sealing member; means for releasing said first portion from said second portion to lower said sealing member into sealing position; and said sealing member being clear of such casing hanger prior to being lowered into said sealing position.
 2. Apparatus according to claim 1 further including means for providing a continuous seal between said first portion and said second portion.
 3. An apparatus according to claim 1 further including means for re-engaging said first portion with said second portion.
 4. An apparatus according to claim 3 wherein said re-engaging means includes a latch means frictionally wedging between said first portion and said second portion.
 5. An apparatus according to claim 1 wherein: said releasing means connects said first portion to said second portioN upon a rotation of said first portion of less than 360*; and said second connection means disconnects said second portion from such casing hanger upon a rotation of said second portion.
 6. An apparatus according to claim 1 wherein said releasing means disconnects said first portion from said second portion upon a rotation of said first portion of less than 360*.
 7. An apparatus according to claim 6 wherein said releasing means includes a breech block connection having tooth segment means in the upper interior of said first portion and correlative tooth segment means on the exterior of said second portion.
 8. An apparatus according to claim 1 in combination with a casing head having a stop means wherein said sealing member includes latch means engageable with said stop means upon rotation of said first portion.
 9. An apparatus according to claim 8 wherein said sealing member includes a tubular member rotatably connected to a retainer member and said latching means includes a latch member supported by an actuator member; said actuator member being reciprocatably mounted on said retainer member thereby preventing rotation relative therebetween and being threadingly engaged to said tubular member whereby upon the rotation of said tubular member said actuator member moves axially on said retainer member forcing said latch member to engage said stop member.
 10. An apparatus according to claim 9 wherein said retainer member includes a packing element whereby said element is compressed against a portion of such casing hanger, thereby sealingly engaging both said casing head and such casing hanger, because of the force applied to said retainer member by said tubular member upon the engagement of said latch member and said stop member.
 11. An apparatus according to claim 10 wherein said retainer member further includes an upper annular ring and a lower annular ring; said packing element being positioned between said rings whereby upon the compression of said packing element, said packing element is compressed radially inward sealingly engaging the exterior of such casing hanger and radially outward sealing engaging the interior of said casing head.
 12. An apparatus according to claim 10 wherein said tubular member is releasably connected to said first portion by said first connection means and said sealing member further includes anti-rotation means for preventing said retainer member from rotating when said sealing member is in the sealing position whereby upon the rotation of said first portion, said tubular member rotates and said retainer member remains stationary.
 13. An apparatus according to claim 12 in combination with such casing hanger wherein said anti-rotation means includes a clutch connection between said retainer member and a portion of said casing hanger.
 14. An apparatus according to claim 13 wherein said clutch connection includes biased lugs reciprocatably mounted on said retainer member for insertion into correlating recesses in said portion of said casing hanger in said sealing position thereby preventing rotation of said retainer member while in said sealing position.
 15. Apparatus comprising a casing hanger having means thereon for supporting a casing therebelow, and means for engaging a surrounding well head for support of the casing hanger on the well head, a running tool extending upwardly from said casing hanger, means on said running tool and said casing hanger for releasably supporting said casing hanger on said running tool, a compressible packoff surrounding a portion of said running tool, and means on said running tool and said packoff for releasably supporting said packoff on said running tool, the latter means comprising a J-slot connection, whereby said running tool and said packoff may be disengaged and re-engaged for support of said packoff by said running tool upon rotation of said running tool less than one turn, said running tool including a releasable conneCtion intermediate the casing hanger support means and the packoff support means which allows movement of said packoff longitudinally relative to said casing hanger when said connection is released.
 16. A method of installing a casing hanger comprising the steps of: suspending a sealing member from a first portion of a well tool and a casing hanger from a second portion of the well tool; lowering the sealing member and casing hanger into the well on the well tool; landing the casing hanger on the previously installed casing head; rotating the first portion to disconnect the first portion from the second portion of the well tool; lowering the first portion and sealing member further into the well; rotating the first portion to set the sealing member within the well; raising the first portion to disconnect the first portion from the sealing member; and rotating the first portion to engage the second portion of the well tool and to disconnect the second portion from the casing hanger.
 17. A method as defined in claim 16 wherein the first portion is always rotated in the same direction.
 18. A method of installing and sealing a casing hanger affixed to and supporting a string of casing in a remote previously installed casing head in a well comprising lowering the casing hanger and a sealing member therefor into the well on a running tool until the casing hanger lands on the casing head, cementing the casing in the well, setting the sealing member, pressure testing the sealing member without removing the running tool, unsetting the sealing member and raising it from the well on said running tool, without removing said casing hanger, and replacing said sealing member with a second sealing member.
 19. A method of installing a casing hanger in a casing head comprising the steps of suspending a sealing member from a first portion of a well tool and a casing hanger from a second portion of the well tool, lowering the sealing member and casing hanger into the well on the well tool, landing the casing hanger on the previously installed casing head, disconnecting the first portion from the second portion of the well tool, lowering the first portion and sealing member further into the well, setting the sealing member within the well, disconnecting the first portion from the sealing member, moving the first portion to engage the second portion of the well tool, disconnecting the second portion from the casing hanger, and raising the first portion and the second portion of the well tool from the well.
 20. Apparatus comprising a casing hanger having means thereon for supporting a casing therebelow, and means for engaging a surrounding well head for support of the casing hanger on the well head, a running tool extending upwardly from said casing hanger, said running tool comprising a first portion and a second portion releasable from each other on manipulation of said running tool, means on the second portion of said running tool and said casing hanger for releasably supporting said casing hanger on said second portion of said running tool, a compressible packoff adapted to provide a seal between said casing hanger and said well head, and means on the first portion of said running tool and said packoff for releasably supporting said packoff on said first portion of said running tool.
 21. Apparatus as defined by claim 20 wherein said second portion of said running tool is telescopically retained within said first portion of said running tool.
 22. Apparatus as defined by claim 21 wherein said second portion of said running tool is connected to said casing hanger by means of a left-hand threaded connection and a shear pin.
 23. Apparatus for setting a casing hanger connected to a casing in a well head located at a remote location below the surface, and setting a packoff to seal between said casing hanger aNd said well head, comprising an elongate rotatable and reciprocable running tool having a length sufficient to extend from the surface to the well head, said running tool having a first portion connected to its lower end and a second portion carried by said first portion, a casing hanger having means thereon for supporting a casing therebelow and means for engaging the well head to support the casing hanger and the casing on the well head, means on the second portion of the running tool and on the casing hanger for releasably supporting the casing hanger, a packoff adapted to provide a seal between said casing hanger and said well head, means on the first portion of the running tool and on the packoff for releasably supporting the packoff on the first portion of the running tool, and a releasable connection between said first portion and said second portion operable upon manipulation of said running tool to permit said first portion to move downwardly relative to said second portion and to be rotated relative to said second portion.
 24. Apparatus as defined by claim 23 wherein said second portion is telescoped within said first portion and carried on a shoulder therein. 